#define _CRT_SECURE_NO_WARNINGS

#include <stdio.h>
int main()
{
	int i = 0,Count=0;
	for (i = 9; i <= 99; i++)
	{
		if (9 == i % 10)
			Count++;
		if (9 == i / 10)
			Count++;
	}
	printf("%d\n", Count);
	return 0;
}
